I’d put my money on her being a liar. The whole thing has smelled of BS from the very beginning. I’d note if you follow the link to Bearing Arms, this is a progressive site reporting on this. Bob Owens notes:

It also remains to be seen if Longdon’s apparent deception will be enough for Moms Demand Action/Everytown to dissociate themselves from her.

Fat chance. They are professional liars themselves. They have no concern for the truth if the media is willing to buy their lies hook, line and sinker.